A sensor interconnect assembly has a circuit substrate. An emitter portion of the substrate is adapted to mount emitters. A detector portion of the substrate is adapted to mount a detector. A cable portion of the substrate is adapted to connect a sensor cable. A first group of conductors are disposed on the substrate electrically interconnecting the emitter portion and the cable portion. A second group of conductors are disposed on the substrate electrically interconnecting the detector portion and the cable portion. A decoupling portion of the substrate disposed proximate the cable portion substantially mechanically isolating the cable portion from both the emitter portion and the detector portion so that sensor cable stiffness is not translated to the emitters or the detector.